parergen: fix bug in deriving itemsets

[ocean] / csrc / parsergen.mdc

diff --git a/csrc/parsergen.mdc b/csrc/parsergen.mdc
index ad20195f51b8f355bc0bca3eebe021eb495106e0..a6486df26025ab252fd4fc446aea2c3dda02e9aa 100644 (file)
--- a/csrc/parsergen.mdc
+++ b/csrc/parsergen.mdc
@@ -1488,18 +1488,21 @@ itemsets (or merged with a pre-existing itemset).
                                continue;
                        if (pr->body[bp] != sym)
                                continue;
+
+                       bp += 1;
                        if (type >= LALR)
                                la = is->items.data[j];
-                       pos = symset_find(&newitemset, pr->head->num);
-                       if (bp + 1 == pr->body_size &&
+                       if (bp == pr->body_size &&
                            pr->precedence > 0 &&
                            pr->precedence > precedence) {
                                // new itemset is reducible and has a precedence.
                                precedence = pr->precedence;
                                assoc = pr->assoc;
                        }
+                       pos = symset_find(&newitemset, item_num(p, bp));
+
                        if (pos < 0)
-                               symset_add(&newitemset, item_num(p, bp+1), la);
+                               symset_add(&newitemset, item_num(p, bp), la);
                        else if (type >= LALR) {
                                // Need to merge la set.
                                int la2 = newitemset.data[pos];
@@ -2303,15 +2306,15 @@ transformed, and will cause an error when the code is compiled.
 ###### functions
 
        static void gen_reduce(FILE *f, struct grammar *g, char *file,
-                              struct code_node *code)
+                              struct code_node *pre_reduce)
        {
                int i;
                fprintf(f, "#line 1 \"gen_reduce\"\n");
                fprintf(f, "static int do_reduce(int prod, void **body, struct token_config *config, void *ret)\n");
                fprintf(f, "{\n");
                fprintf(f, "\tint ret_size = 0;\n");
-               if (code)
-                       code_node_print(f, code, file);
+               if (pre_reduce)
+                       code_node_print(f, pre_reduce, file);
 
                fprintf(f, "#line 4 \"gen_reduce\"\n");
                fprintf(f, "\tswitch(prod) {\n");
@@ -2446,7 +2449,7 @@ grammar file).
                case 't':
                        tag = optarg; break;
                default:
-                       fprintf(stderr, "Usage: parsergen ...\n");
+                       fprintf(stderr, "Usage: parsergen -[05SL1R] [-t tag] [-o output] input\n");
                        exit(1);
                }
        }